Representatives of 1,200 ambulance personnel were meeting the HSE this afternoon to discuss emergency cover arrangements during a nationwide strike planned for 7 April.
The ambulance personnel are in dispute with the HSE after it signed contracts with three private ambulance operators.
SIPTU says the HSE's move breaches an existing agreement. It says the HSE had agreed to fully consult the union before signing any such contracts.
The HSE denies the contracts are part of a move to privatise the ambulance service.
It says the new service is intended to transport non-emergency patients between hospitals and other health units.
The HSE says the total budget for the national ambulance service is €146m, while less than €5m is spent on private services.
It says it remains committed to investment in the public ambulance service, but that highly trained emergency medical technicians are better deployed to frontline casualty services.
The Labour Relations Commission could intervene in the dispute, which could cause significant disruption to patients if it goes ahead.
